System and method for information handling system wireless audio driven antenna

ABSTRACT

Audio information coexists with best efforts data on a wireless network, such as a wireless local area network, by defining a backoff dedicated to communicate of audio information and using undedicated resources to communicate best efforts data. The backoff has a periodic interval that corresponds to the sample rate of the audio information so that a set of audio frame slots communicated at the start of a backoff interval has a length of time to complete communication. The set of audio frame slots has, for instance, an audio frame slot for each audio endpoint interfaced with the network. Periodic backoffs ensures synchronized audio playback by dedicating an antenna to communication of audio frames at the sample rate of the audio information, while supporting best efforts network communication when audio information is not being communicated.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates in general to the field of informationhandling system wireless communication, and more particularly to asystem and method for information handling system wireless audio drivenantenna.

2. Description of the Related Art

As the value and use of information continues to increase, individualsand businesses seek additional ways to process and store information.One option available to users is information handling systems. Aninformation handling system generally processes, compiles, stores,and/or communicates information or data for business, personal, or otherpurposes thereby allowing users to take advantage of the value of theinformation. Because technology and information handling needs andrequirements vary between different users or applications, informationhandling systems may also vary regarding what information is handled,how the information is handled, how much information is processed,stored, or communicated, and how quickly and efficiently the informationmay be processed, stored, or communicated. The variations in informationhandling systems allow for information handling systems to be general orconfigured for a specific user or specific use such as financialtransaction processing, airline reservations, enterprise data storage,or global communications. In addition, information handling systems mayinclude a variety of hardware and software components that may beconfigured to process, store, and communicate information and mayinclude one or more computer systems, data storage systems, andnetworking systems.

Information handling systems have transformed the way enterprisesoperate as well as how individuals run households. Initially,information handling systems managed financial information and wordprocessing functions. Since their introduction, the growth of theInternet has made information handling systems one of the primarycommunication tools of enterprises and households through the use ofe-mail and the Internet. More recently, information handling systemshave transitioned into the role of entertainment, such as by storing andplaying music and movies. As information handling systems have come tomanage audio information storage and presentation, end users have soughtconvenient ways to communicate audio information from an informationhandling system that generates audio information to audio endpoints thatpresent audio information. One difficulty to deploying audio endpointsis the running of wires between audio sources and audio endpoints. Anoption to avoid the use of wires is to use wireless communication, suchas through a wireless local area network (WLAN) like those defined byIEEE 802.11(b, g or n) or wireless personal area network (WPAN) likeBluetooth. A difficulty with wireless communication of audio informationfrom an audio source to an audio endpoint is that wireless communicationtends to have poor quality of service and synchronization coordinationneeded for audio distribution to multiple audio endpoints, such asmultiple speakers that play in stereo.

Recently, audio oriented wireless systems have emerged which addressquality of service needs, but compete for bandwidth with data servicescommunicated through the same or similar wireless bands. Generally,wireless networks transmit data on a best efforts basis; however, audioinformation tends to degrade when sent through best efforts networksbecause a missing frame of audio information is detectable by an enduser listening to an audio presentation. Audio frames typically have atarget sample rate or a multiple of a sample rate with the collection ofthe samples at an endpoint presenting a desired audible sound. In orderfor audio information to maintain a desired quality, real-time deliveryof audio frames synchronized for all end points is desired with areliable distribution through a wireless communication medium. Existingmethods of maintaining reliable audio distribution include adaptivefrequency hopping, which attempts to maintain communication of audioinformation through a clean frequency, channel avoidance, which attemptsto maintain a channel free for communication of audio information andMAC address level signaling. A more expensive option is to dedicate anantenna for audio communication, however, the use of existing bandwidthswith a dedicated antenna can still have degraded communications due tocompetition within the frequency band.

SUMMARY OF THE INVENTION

Therefore a need has arisen for a system and method which allows audioinformation to coexist on a wireless network with best effortsinformation.

In accordance with the present invention, a system and method areprovided which substantially reduce the disadvantages and problemsassociated with previous methods and systems for communication of audioinformation through a wireless network. A periodic backoff intervalcorresponds with the sample rate of audio information. An audio frame issent through the wireless network at the start of each backoff for abackoff length sufficient to complete the communication of the audioinformation. The remainder of the audio frame is then used for bestefforts network communication.

More specifically, an information handling system is built from pluralprocessing components that cooperate to process information, such asaudio information for presentation at audio endpoints, like as speakers.The audio information coexists on a wireless network with best effortsformatted information by defining periodic backoffs during which only orsubstantially only audio information is sent through the wirelessnetwork. A backoff module running on a processor and memory of theinformation handling system defines the backoff to have a periodicinterval that corresponds to the sample rate of the audio information sothat an audio frame is communicated across the wireless network at thestart of each backoff interval. The backoff has a length sufficient tocommunicate an audio frame of the quality and the number of slots neededfor the audio information. After the length passes and the audioinformation of the audio frame is communicated, the remainder of timeuntil the start of the next backoff is available for communicatingnetwork information on a best efforts basis.

The present invention provides a number of important technicaladvantages. One example of an important technical advantage is thataudio information with real time communication demands coexists withbest efforts data on a wireless network. By defining a periodic backoffwith an interval that corresponds to the sample rate of audioinformation, adequate bandwidth is reserved on a real time basis tosupport an audio stream to one or more audio endpoints, such asspeakers. Once audio information is sent for a frame, the remainder oftime until the next frame is available to send best efforts data.Synchronized audio information is communicated on a real time basis byreducing interference and bottlenecks that could result from bestefforts network traffic so that audio quality at an end point ispreserved. A backoff is optionally enforced across a wireless network,such as by communicating the backoff to each device of the wirelessnetwork, to maintain a reliable interface of audio information on a realtime basis.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention may be better understood, and its numerousobjects, features and advantages made apparent to those skilled in theart by referencing the accompanying drawings. The use of the samereference number throughout the several figures designates a like orsimilar element.

FIG. 1 depicts a block diagram of an information handling systemconfigured to communicate audio information using periodic backoffintervals; and

FIG. 2 depicts a flow diagram of a process for communicating audioinformation using periodic backoff intervals; and

FIG. 3 depicts audio frame slots for plural audio endpoints during abackoff interval.

DETAILED DESCRIPTION

Using a backoff at an antenna to enforce exclusive use of the antenna tocommunicate audio information from an information handling system toaudio endpoints through a wireless network during the backoff providescoexistence of audio and best efforts data at the network. For purposesof this disclosure, an information handling system may include anyinstrumentality or aggregate of instrumentalities operable to compute,classify, process, transmit, receive, retrieve, originate, switch,store, display, manifest, detect, record, reproduce, handle, or utilizeany form of information, intelligence, or data for business, scientific,control, or other purposes. For example, an information handling systemmay be a personal computer, a network storage device, or any othersuitable device and may vary in size, shape, performance, functionality,and price. The information handling system may include random accessmemory (RAM), one or more processing resources such as a centralprocessing unit (CPU) or hardware or software control logic, ROM, and/orother types of nonvolatile memory. Additional components of theinformation handling system may include one or more disk drives, one ormore network ports for communicating with external devices as well asvarious input and output (I/O) devices, such as a keyboard, a mouse, anda video display. The information handling system may also include one ormore buses operable to transmit communications between the varioushardware components.

Referring now to FIG. 1, a block diagram depicts an information handlingsystem 10 configured to communicate audio information using periodicbackoff intervals. Information handling system 10 is built from pluralprocessing components that cooperate to process information, such asgeneration of audio information for presentation at audio endpoints likespeakers 12. For example, information handling system 10 has a CPU 14that processes information stored in RAM 16 or a hard disk drive 18. Achipset 20 coordinates the interaction of the processing components at aphysical level. In one embodiment, an application executing on CPU 14retrieves audio files 22 stored in non-volatile memory of hard diskdrive 22 and processes audio information of audio files 22 into audioframes for presentation at speakers 12. In an alternative embodiment, anaudio processor 24 associated with chipset 20 processes audio filesretrieved by CPU 14 from hard disk drive 18 and placed in RAM 16. Audioframes are communicated from information handling system 10 by awireless network device 26, such as a wireless network interface card,through a wireless network 28, such as a wireless local area network(WLAN) as defined by IEEE 802.11(b, g or n) or a wireless personal areanetwork (WPAN) like Bluetooth.

Audio frames sent through wireless network 28 are synchronized and senton a real time basis so that the presentation of sounds from speakers 12is coordinated. In order to ensure that audio frames successfullycoexist with other network data that is transmitted on a best effortsbasis, a backoff module 30 associated with wireless network interfacecard 26 dedicates exclusive network use for the audio frames duringperiodic backoff intervals that correspond to the sample rate of theaudio frames and for a length that allows communication of plural audioslots of an audio frame with an audio slot having information for one ormore of each audio endpoint during the backoff interval. Backoff module30 is, for example, a software driver executing on CPU 14 and stored inmemory, such as RAM 16, or persistent memory, such as within anoperating system stored on hard disk drive 22. Once the backoff lengthhas expired for a backoff interval, the backoff module permits besteffort data transmission over wireless network 28 until the next backoffinterval period begins. The wireless network thus transitions at eachperiodic backoff interval to exclusive transmission of audio informationon a real time basis for the length needed to communicate an audio frameslot for each audio endpoint, and uses the remaining time until the nextinterval begins to communicate best efforts network data. In oneembodiment, backoff module 30 sets a minimum amount of time for theavailability of wireless network 28 for best efforts communication andthen sets a quality level for the audio information so that the periodicbackoff interval and length allow the set minimum time for best effortscommunication of data over wireless network 28. By restrictingcommunications to audio information during a backoff length of time, anantenna 29 sends only audio information transmissions during those timeswhen audio frames are sent on a real time basis so that interference atantenna 29 is minimized. In one embodiment, backoff module 30 providesthe periodic backoff intervals and lengths to other wireless devices ofwireless network 28 so that the other devices also restrictcommunications when audio frames are sent.

Referring now to FIG. 2, a flow diagram depicts a process forcommunicating audio information using periodic backoff intervals. Theprocess begins at step 32 with analysis of an audio information samplerate for audio frames to be sent over the wireless network in order todetermine a periodic backoff interval. The periodic backoff intervalcorresponds to the real time transmissions needed to match the samplerate of the audio frames. Higher quality sound with greater sample rateswill have shorter backoff intervals with more frequent transmissions ofaudio frames. In one embodiment, buffering of information can be used tosend multiple samples of audio data in one audio frame to allow a longerbackoff interval with more bits per frame. At step 34, the audioquality, such as bits per sample, is analyzed to determine a backofflength that is sufficient to include a set of audio frame slots sent ina backoff interval. The backoff length will increase as the number ofaudio frame slots increases, such as with a greater number of endpoints,or with greater audio quality, such as HD quality having a larger audioframe slot for each endpoint compared with CD quality having smalleraudio frame slots. At step 36, the backoff interval and length areadjusted in order to ensure a desired minimum bandwidth or transmissiontime for sending best efforts data. For example, if a minimum setting ofbest efforts network capacity is not available for a given transmissionof audio information, the size of the audio transmission is reduced toleave greater transmission time for best efforts data. For instance, thesize of the audio transmission is reduced by reducing the sample rate oraudio quality (bits per sample).

At step 38, the start of a backoff interval is detected, such as withthe start of audio information transmission through a wireless network.At step 40, communications are restricted at the wireless network totransmissions of audio frames for the backoff length. Restrictingcommunications to exclude all but audio information during the backofflength avoids interference with other transmissions and ensures realtime delivery of synchronized audio information. During the periodicbackoff interval length, only or substantially only audio information istransmitted through wireless antenna of an information handling systemfor communication over a wireless network. At step 42, transmissions atthe information handling system antenna returns to a best effortsformat, such as is commonly associated with wireless local areanetworks, until the end of the backoff interval period. The processreturns to step 38 at the start of the next periodic backoff interval toagain initiate communication of audio information. Once communication ofaudio information is complete, the backoff module ceases backoffintervals so that the antenna communicates at a best efforts formatwithout setting aside time for communication of audio information.

Referring now to FIG. 3, audio frames 44 having slots 46 for pluralaudio endpoints during a backoff interval are depicted. In the exampleembodiment of FIG. 3, the audio frame sample rate is 48 KHz sent acrossan IEEE 802.11 (n) wireless local area network having a bandwidth of 100Mbps so that each audio frame has a total duration of 20.83 microsecondswith a total potential data load of 2083 bits. A periodic backoffinterval of 20.83 microseconds ensures that at the start of each backoffinterval an audio frame 44 has audio information for communicationacross the wireless network. An audio slot 46 carries audio informationfor an audio endpoint or a set of audio endpoints that use the same dataso that an audio slot 46 is sent in each audio frame 44 for eachsupported endpoint or set of endpoints. In addition, some audio controldata or synchronization data 50 may be sent with each frame 44. With CDquality audio information, each audio slot 46 has 32 bits while with HDquality audio information, each audio slot has 128 bits. For a typicalsetup with four endpoints, four audio slots 46 of information are sentwith each audio frame. For a CD quality communication, each audio frame44 will send four slots 46 of 32 bits each for a backoff length of 128bits, consuming only approximately 6% of the bandwidth of the frame andleaving 94% of the frame (1955 bits) for best efforts communication. Fora HD quality communication, each audio frame 44 will send four slots 46of 128 bits each for a backoff length of 512 bits, consuming onlyapproximately 25% of the bandwidth of the frame and leaving 75% of theframe (1315 bits) for best efforts communication.

Although the present invention has been described in detail, it shouldbe understood that various changes, substitutions and alterations can bemade hereto without departing from the spirit and scope of the inventionas defined by the appended claims.

1-20. (canceled)
 21. A method for communicating audio informationthrough a wireless network, the method comprising: communicating audioframes through the wireless network to plural audio endpoints duringbackoffs, the plural audio endpoints presenting sounds insynchronziation with each other; restricting communication of data otherthan the audio frames during the backoffs; communicating data in a bestefforts format outside of the backoffs; and presenting the audio soundssynchronized at the plural audio endpoints.
 22. The method of claim 21wherein communicating audio frames and communicating data furthercomprise communicating the audio frames and data with the wirelessnetwork through a common antenna.
 23. The method of claim 22 wherein thenetwork comprises a wireless local area network.
 24. The method of claim22 wherein the network comprises a wireless personal area network. 25.The method of claim 21 wherein the each backoff comprises 32 bits peraudio frame.
 26. The method of claim 21 further comprising: defining abackoff for each of the plural audio endpoints; and communicating anaudio frame through the wireless network at each backoff, each audioframe having plural audio slots, each audio slot associated with oneaudio endpoint.
 27. The method of claim 26 wherein the audio endpointscomprise speakers.
 28. The method of claim 21 further comprising:setting a minimum time period for communicating data in a best effortsformat; and adjusting the backoffs to maintain the wireless network forcommunicating in a best efforts format for at least the minimum timeperiod.
 29. The method of claim 28 wherein adjusting further comprisesreducing the quality of audio information in the audio frame to reducethe backoff length.
 30. An information handling system comprising: aprocessor operable to generate audio information; a wireless networkdevice interfaced with the processor and operable to communicate theaudio information through a wireless network to plural audio endpoints,the plural audio endpoints operable to present audio sounds insynchronization with each other; and a backoff module interfaced withthe wireless network device, the backoff module operable to definebackoffs at the wireless network, the backoffs for communication of theaudio information, the backoff module further operable to communicatedata in a best efforts format outside the backoffs.
 31. The informationhandling system of claim 30 wherein the audio information comprisesplural audio frames, each of the plural audio frames having pluralsynchronized audio slots with one slot for use by each set of audioendpoints.
 32. The information handling system of claim 31 wherein theaudio endpoints comprise stereo speakers.
 33. The information handlingsystem of claim 32 wherein the wireless network device comprises anantenna system that communicates both the audio frame and data.
 34. Theinformation handling system of claim 30 wherein the backoff module isfurther operable to set a minimum time for communication of data in abest efforts format.
 35. The information handling system of claim 34wherein the backoff module sets a minimum time for communication of datain the best efforts format by setting a maximum audio length associatedwith a predetermined audio quality.
 36. The information handling systemof claim 35 wherein the wireless network comprises a wireless local areanetwork.
 37. A method for communicating audio frames and best effortsdata through a common antenna system, the method comprising: defining abackoff having a length sufficient to communicate a predetermined sizeof audio information; communicating audio information with pluralbackoffs at predetermined periodic intervals; restricting communicationthrough the common antenna system to the audio information the pluralbackoffs; presenting audio in stereo at the plural audio endpoints withthe audio information; and communicating best efforts data through thecommon antenna system outside the plural backoffs.
 38. The method ofclaim 37 wherein the predetermined periodic intervals correspond to asample rate of the audio information.
 39. The method of claim 37 whereinthe audio information comprises an audio frame slot for each of pluralaudio endpoints.
 40. The method of claim 37 wherein the antennacommunicates through a wireless local area network.